#[cfg(test)]
mod tests {
    use crate::Stack;

    #[test]
    fn test_list() {
        let mut stack = Stack::new();
        assert_eq!(stack.is_empty(), true);
        stack.push(1);
        stack.push(2);
        stack.push(3);

        assert_eq!(stack.pop(), Some(3));
        assert_eq!(stack.pop(), Some(2));
        assert_eq!(stack.pop(), Some(1));
        assert_eq!(stack.peek(), Option::None);
        // assert_eq!(list.pop(), None);
    }
}
